Lateral Pressure Distribution Research Articles

Modified kinematic alignment better restores plantar pressure distribution than mechanical alignment in total knee arthroplasty: a randomized controlled trial

Kinematic alignment (KA) in the short to medium term clinical outcomes is superior to the mechanical alignment (MA), but whether it will improve patients’ postoperative gait is still controversial. Understanding whether and how KA influences postoperative gait mechanics could provide insights into optimizing alignment philosophy to improve functional outcomes. To investigate the impact of KA versus MA in total knee arthroplasty (TKA) on the operated and contralateral native lower limbs by analyzing plantar pressure distribution during walking gait. This study was designed as a secondary analysis from a randomized controlled trial. Thirty-seven patients were included, nineteen underwent KA-TKA and eighteen underwent MA-TKA, each with a native knee in the contralateral limb. Pressure-sensitive insoles were used to collect plantar pressure distribution of both limbs simultaneously during walking defined as medial-lateral load ratio (MLR). Perioperative characteristics including radiographic metrics (Hip-Knee-Ankle angle (HKA), mechanical lateral distal femoral angle (mLDFA), and mechanical medial proximal tibial angle (mMPTA) and clinical outcomes (Oxford Knee Scores (OKS)) were compared between the two groups pre-operatively and 2-year postoperatively. Significant differences were found in postoperative radiographic metrics, with KA showing better OKS 1 year postoperatively (p = 0.021), lower mean HKA (p = 0.009) and mMPTA (p < 0.001). Other perioperative characteristics were similar between groups. In the pedobarographic analysis, the MA group demonstrated greater medial pressure distribution in forefoot compared to both the KA group (p < 0.001) and the contralateral native knee (p = 0.002). Besides, the MA group revealed a more lateral pressure distribution in rearfoot compared to the KA group (p = 0.007) and the contralateral native knee (p = 0.001). While there was no significant difference between KA and native group (p = 0.064 and p = 0.802, respectively). KA offered advantages over MA in restoring a more physiologic plantar pressure distribution at two years postoperatively. These results underscore the potential clinical benefits of adopting KA techniques in TKA procedures.

Detection of Stress Distribution in Surrounding Rock of Coal Seam Roadway Based on Charge Induction Principle

Rock burst is a worldwide prevention and control problem, and the main reason for its occurrence is the concentration of stress in the surrounding rock of the coal roadway. Therefore, it is of great significance to realize the rapid and accurate detection of the stress distribution in the surrounding rock of the roadway for the prevention and control of rock burst. Based on the principle of charge induction, this paper adopts a research method combining theoretical analysis and indoor and field tests to carry out a study on the charge induction detection of stress distribution of surrounding rock in coal seam roadways using the self-developed coal rock charge induction monitor. A theoretical analysis of the charge induction intensity in relation to the stress level is carried out. Indoor tests on the law of charge induction for graded loading of large sized coal samples are carried out. Field detection tests of the charge induction law at different drilling depths on the solid coal side and the large coal pillar side of the coal seam roadway are carried out. The results show a positive correlation between the charge signal intensity and the stress magnitude. The induced charge of coal samples has a tendency to increase with the increase in graded loading stress level. The magnitude of the induced charge can reflect the stress level of the coal body. On the solid coal side, the induced charge has a tendency of increasing and then decreasing with the increase in detection depth. The final results are in good agreement with the results of the drill chip method, which better reflects the distribution of the lateral support pressure of the roadway. On the side of the large coal pillar, the induced charge has a tendency to increase, then decrease, and then increase with the increase in probing depth, which is in good agreement with the distribution of lateral support pressure formed in the elastic core area of the large coal pillar. Therefore, the charge induction technology can be used as a fast, non-contact detection means for the partitioning and stress distribution of the roadway enclosure, which can provide guidance for the target prevention and controlling rock burst and for designing roadway support.

Risk-based asset management framework for highway retaining wall systems using wireless structural health monitoring data

Retaining walls are important structural systems used in the construction of highways. With asset management methods for retaining wall inventories lagging those developed for highway bridges, there is a need to develop risk management methods for these critical structural systems. A major challenge is the vast inventories of retaining walls that asset managers must manage and the inherent limitations of visual inspections. This study proposes an asset management framework for retaining walls based on risk assessments using structural monitoring data. First, a long-term wireless monitoring solution is proposed to measure wall tilt and strain over long periods of time. Second, an analytical framework is developed to separate wall thermal responses from lateral earth pressures responses with the latter used to extract estimated lateral earth pressure distributions. A statistical distribution of lateral earth pressures are used in a reliability assessment of the wall to provide a measure of failure probability that can be combined with failure consequences to estimate asset risk. To illustrate the proposed methodology, a reinforced concrete cantilever retaining wall panel is selected for long-term structural health monitoring. A wireless structural health monitoring system is installed to measure the tilt, strain, and temperature response of the wall continuously over 15 months. The study reveals the wall exhibits strong diurnal and seasonal variations offering insight into wall behavior under operational conditions. Hypothesized levels of corrosion in the steel reinforcement at the base of the wall are explored to estimate the wall reliability. Even under the assumption of 20% reinforcement section loss, the monitored wall was found to have a reliability index well above 3.0.

Surgical management of severe planovalgus foot deformity in children with generalised joint hypermobility

BackgroundThis study aimed to evaluate the outcomes of calcaneal lengthening osteotomy (CLO) and double arthrodesis of the talonavicular and calcaneocuboid joints (DA) for correcting planovalgus foot deformity exclusively in patients with generalised joint hypermobility. MethodsWe retrospectively reviewed 29 feet in 17 consecutive patients who underwent either CLO or DA. The mean age at surgery was 11.3 ± 2.3 years, and the mean follow-up duration was 7.7 ± 3.2 years. Preoperative and final follow-up radiographs and dynamic foot-pressure measurements were analysed. ResultsBoth operations significantly improved the radiographic parameters, except for the lateral talocalcaneal angle in the CLO group. Pedobarographic study demonstrated an elevation of the medial longitudinal arch and an improved foot-pressure distribution after both surgeries. The plantar pressure in the lateral forefoot significantly increased only in the DA group, while the pressures exerted on the medial forefoot and hindfoot and the arch index improved only in the CLO group. ConclusionsBoth CLO and DA effectively improve the foot alignments of the deformity in patients with generalised joint hypermobility. However, differences were observed in the changes in the lateral talocalcaneal angle and plantar pressure distribution between the two procedures. Level of evidenceTherapeutic Level III.

Soil-structure interaction issues in integral abutment bridges

Integral Abutment Bridges (IABs) are constructed without expansion joints and bearings, connecting the bridge deck monolithically to the end abutments. Therefore, the construction and maintenance costs of IABs are low compared to conventional bridges with bearings and joints. However, the soil-structure interaction issues are more complex for IABs due to the transfer of deck movements to the foundations through the abutments. Hence abutments of these bridges play an important role in the performance of the substructure and consequently the design approach for the substructure. In this paper, soil-structure interaction issues are investigated for the deck movements due to cyclic thermal loading, which occurs as a combination of daily and seasonal temperature changes. The development of a physical model facility to simulate the problem is described with scaling laws and material properties. The settlement problem at the bridge approach and stress ratcheting phenomena observed at the abutment soil interface are discussed using results from model tests. For the prediction of lateral earth pressure distribution behind abutments, currently available methods are discussed, and modifications are proposed. Finally, the effectiveness of Expanded Polystyrene (EPS) geofoam as an inclusion is discussed to mitigate approach settlement and stress ratcheting problems due to cyclic thermal loading. The results of this study confirm that EPS geofoam is a highly effective material to minimise adverse soil-structure interaction issues in integral bridge abutments.

A Fully Prefabricated Pile-Wall Composite Scheme of Open-Cut Tunnel and the Mechanical Behavior of the Composite Structure during Construction

In open-cut assembled subway tunnels, foundation pit enclosure piles are typically cast in place. However, this conventional approach limits the functionality of the piles to serving as retaining structures during excavation, resulting in resource inefficiency and the underutilization of prefabrication techniques. To address this issue, a fully prefabricated pile-wall composite scheme is proposed for cut-and-cover tunnels to optimize the retaining effect of the piles and leverage the benefits of prefabricated technology. In this scheme, the retaining pile and lining are both prefabricated. The pile is the temporary retaining structure during pit excavation and a part of the sidewall. This scheme was researched and applied in Jinan, China. Field monitoring and numerical simulation were used to investigate the load transfer within the fully prefabricated pile-wall composite structure (PPWS) and its mechanical response, respectively. The results show: (1) The development of lateral earth pressures on the PPWS experienced three stages. The lateral earth pressure distribution indicates that the PPWS can fully activate the retaining effect of precast piles. (2) Following the backfilling of the joints, the horizontal displacement at the bottom of the precast pile reduced by 0.39 mm. Numerical simulation results indicate the effectiveness of precast pile restraint in PPWS. (3) The PPWS exhibited uniform deformation transition at the joints. The joints play a crucial role in coordinating deformation between the precast piles and sidewalls, utilizing the restraining effect of the precast piles.

Form pressure exerted by concrete for a large-scale structure: Its quantification and physicochemical interpretation

Securing safety in formwork is one of the most important tasks to be carried out in the initial stage of construction. The form pressure exerted by fresh concrete needs to be identified, and it should be retained by a formwork system. A design pressure is given in literature and standards, but for large structures its precise prediction is required through a detailed analysis or a mock-up test. This study reports the lateral form pressure distribution generated by fresh concrete through a series of mock-up tests. The tests are designed considering the placement for nuclear containment structures; 3.4 m tall and 1.2 m thick concrete wall. The experimental program includes the measurements of setting and temperature of concrete samples in addition to the lateral pressure measurement. The maximum form pressure during layer-by-layer placements depends on the concrete temperature and setting time. These are compared with conventional prediction formulas specified in ACI 347 and DIN 18218. Finally, this paper proposes the simplified prediction formula for maximum form pressure based on concrete temperature.

Performance of Pile–Wall System Adjacent to Footings

The performance of a retaining wall is dependent on multiple factors including lateral earth pressure, which results from backfill soils and adjacent footings located behind a retaining wall. The prediction of a retaining wall’s performance in a footing–soil–wall system (FSPS) must incorporate the influences caused by the movement of a retaining wall. This study examines the performance of a retaining wall formed by driven, precast, concrete piles located adjacent to a concrete footing using two- and three-dimensional finite element analysis (2D and 3D FEA) by ANSYS 13.0 software. Both soil and concrete are assumed to behave as non-linear, elastic-perfectly plastic and rate-independent materials in compliance with the upper-bound model of Drucker–Prager yield criterion. Three backfill and foundation soils are considered: kaolin, silty clay, and kaolin–sand. Various conditions of soil type, footing shape ratio, pile width, and footing–pile distance through 180 FEA runs are investigated. The effects of 2D and 3D FEA on the behavior of the pile–wall system are compared. The lateral deflection and pressure distribution profiles along the pile–wall are studied and presented. Two empirical equations predicting lateral deflections at the pile toe and pile head and useful for pile structural design are developed under the ultimate pressure of the adjacent footing.

Effects of cornering conditions on the aerodynamic characteristics of a high-performance vehicle and its rear wing

This study investigates the aerodynamic behavior of a high-performance vehicle and the interaction with its rear wing in straight-line and steady-state cornering conditions. Analyses are performed with Reynolds-averaged Navier–Stokes based computational fluid dynamics simulations using a moving reference frame and overset mesh technique, validated against moving ground wind tunnel experiments. The results indicate a significant 20% decrease in downforce and 35% increase in drag compared to straight-line conditions at the smallest considered corner radius of 2.9 car-lengths. Downforce losses primarily stem from performance deficits on the underbody and rear wing, alongside elevated upper body lift. Drag penalties mainly result from additional pressure drag induced by a recirculation wake vortex generated behind the vehicle's inboard side. The vehicle's lateral pressure distribution is also affected, introducing a centripetal force that increases with smaller corner radii. Additionally, analyses of the rear wing reveal alternations of its aerodynamic characteristics in cornering, particularly impacting vortical flow and suction on the lower surface. Throughout the operating conditions, the rear wing's individual downforce contribution falls off beyond its stall angle. At higher angles of attack, the rear wing primarily generates downforce by pressurizing the vehicle's upper surfaces, but its interaction with the near-wake leads to a substantially increased pressure drag. Overall, these findings provide crucial insights into the intricate aerodynamic interactions of high-performance vehicles in diverse operating conditions as well as form an essential foundation for future research on static and active aerodynamic designs in the pursuit to optimize vehicle performance in dynamic driving conditions.

Experimental Investigation of the Effect of Strip Footing on Shear Band Development and Lateral Pressure Distribution in Helical Soil-Nailed Walls

Experimental Investigation of the Effect of Strip Footing on Shear Band Development and Lateral Pressure Distribution in Helical Soil-Nailed Walls

Observed soil arching-induced ground deformation and stress redistribution behind braced excavation

This paper presents observed arching-induced ground deformation and stress redistribution behind braced excavation using the top-down construction method. The soil properties around the excavation were determined by laboratory and field tests. The ground deformation, soil displacement vector, strain path, principal strain, maximum shear strain, lateral earth pressure, pore water pressure, and effective stress path are presented based on the measured data. The majority of soil behind the wall is under volumetric expansion, indicating consolidation, creep behavior, or a combination of both. Besides, two periods of increases in pore pressure are observed, due to stress transfer from the lower to the upper parts (i.e., soil arching effect). The deep inward movement of the wall and the nearby soil accounts for the distribution of lateral earth pressure acting on the wall. The soil located behind the area of maximum wall deformation and adjacent to the wall, as well as the soil below the excavation base intersected by the shear plane, is in an active stress state. The lateral earth pressure at 5 m from the left excavation wall showed minimal changes, due to the combined effects of soil arching from lateral excavation and shield tunneling.

Study on Non-Limited Earth Pressures of Soilbag-Reinforced Retaining Structures with Surcharge Loads.

The earth pressure acting on soilbag-reinforced retaining structures subjected to surcharge loads under non-limited states is crucial for designing these structures. In this study, mode tests on soilbag-reinforced retaining walls were conducted to the earth pressure of the wall subjected to surcharge loads. The findings from these tests reveal a non-linear distribution of lateral earth pressure on the wall when subjected to surcharge loads in non-limited states, with an observed escalation in pressure corresponding to increased surcharge loads. Insights from the tests facilitated the development of a predictive method for estimating lateral pressure on soilbag-reinforced retaining walls under similar conditions, and its performance was fully validated by the model tests. Furthermore, the impact of the geometric dimensions and material properties of the soilbags on the earth pressure distribution was examined using the proposed method.

Dynamic analysis of MSE wall subjected to surface vibration loading

Abstract Extensively used Mechanically Stabilized Earth (MSE) walls in Rail Transportation System (RTS) are vulnerable to surface vibrations generated by moving vehicles. Hence, it is necessary to consider the effects of surface vibrations during the design of MSE walls for RTS. Steel-reinforced panel-type MSE walls are shown to perform well during vibration loading, but costly steel materials have led to greater reliance on affordable and readily available geosynthetics for reinforcement. Limited research exists on the behavior of panel-type MSE walls with geosynthetics considering RTS-induced vibrations frequencies. Thus, this study employs Finite Element software PLAXIS 3D to simulate the impact of surface vibration frequencies on panel-type MSE walls. The qualitative study encompasses two reinforcement cases (geogrids and steel strips) of 4 m MSE wall height and four harmonic loading frequencies representing RTS-induced surface vibrations for simulation. The dynamic responses of MSE wall are presented in terms of lateral wall displacements and lateral earth pressure distributions. Furthermore, the distributions of tensile strain and the identification of potential slip surface locations are presented. The findings indicated that MSE wall and reinforcement responses are governed by RTS-induced vibrations and fundamental frequency of backfill soil. This highlights the need for consideration of both the fundamental frequency of the backfill soil and RTS-induced vibrations in the design of MSE walls.

At-rest lateral earth pressure in compacted silica sand

ABSTRACTAt-rest lateral earth pressure is one of the major sources of disturbing force on retaining structures and provides resisting force for anchors and piles. A theoretical model is proposed, and experimentally validated, for the normally and overconsolidated at-rest lateral earth pressure coefficients in silica sand. In addition, the experiment illustrates a procedure to determine the maximum historic vertical stress equivalent to the standard and modified Proctor energies of compaction. The previous equivalent maximum historic vertical stress, which is found to be constant for the relative density reached by each energy of compaction, is then proposed as a parameter to determine the overconsolidation ratio within the backfill and its resultant at-rest lateral earth pressure distribution behind a vertical wall. The at-rest lateral earth pressure distribution incorporated with the overconsolidation ratio naturally results in a greater magnitude and is curved in contrast to the linear distribution characteristic of a normally consolidated state. A limit equilibrium analysis and a plane-strain particle-scale model of a granular media under critical state were used to derive the equations herein.

Failure Mechanism and Deformation-Based Design of Narrow Geosynthetic Reinforced Soil Walls

In recent years, the working performance of mechanically stabilized earth (MSE) walls has shown their outstanding stability and capacity to accommodate large deformation. The behavior and failure mechanisms of conventional MSE walls have been carefully examined. In cases where space is limited, such as in mountainous regions, in coastal regions, and for road expansion, the conventional MSE wall can be modified by adjusting the length of reinforcement to conform the construction area. For narrow geosynthetic reinforced soil (GRS) wall, the modification and arrangement of reinforcement components, including reinforcement tensile strength, vertical spacing, and aspect ratio, play key roles in the behavior of reinforced earth walls and can also lead to differences in the distribution of lateral earth pressure compared with conventional MSE walls. In this study, a series of geotechnical centrifuge tests are conducted to clarify the failure behaviors, distribution of lateral earth pressure, and deformation progresses of narrow GRS walls. Among the investigated variants, it is verified that improved reinforcement strength leads to a significant decrease in horizontal wall displacement. The relationship among lateral earth pressure, zero-earth-pressure zone, and horizontal displacement can be applied to predict the deformation of a narrow GRS wall.

Determination of Passive Earth Pressure on a Cantilever Retaining Wall in a Narrow Foundation Pit Based on Logarithmic Spiral Sliding Surface

The distribution of passive earth pressure on a cantilever flexible retaining wall in a narrow foundation pit is significantly affected by the adjacent retaining wall and the width of the foundation pit. The deformation mode of the cantilever retaining wall rotating around the displacement zero point makes the soil layer below the displacement zero point retain a nonlimit passive state. The functional relationship between soil mechanical parameters and horizontal displacement in the nonlimit state region, considering the influence of displacement, is established. A new combined failure mode of the soil mass in the passive zone of the narrow foundation pit is proposed, which is the logarithmic spiral fracture surface in the nonlimit state region and the broken line fracture surface in the limit-state region. On this basis, a passive earth pressure calculation model of a narrow foundation pit is proposed and solved by differential layer method. The solution of the passive earth pressure coefficient strictly meets the static equilibrium conditions in vertical and horizontal directions as well as the moment equilibrium conditions. A numerical example is used to analyze the influence of the width of the foundation pit. The smaller the narrow foundation pit width, the greater the passive earth pressure in the lower soil layer and it even greatly exceeds the Coulomb earth pressure distribution. The earth pressure distribution acting on the lower part of the wall near the zero point of displacement decreases sharply and bends. The passive earth pressure distribution is calculated by the theoretical method and compared with the laboratory model test results as well as the engineering test results. It is found that the proper selection of the initial soil mechanical parameters affects significantly the magnitude and distribution of lateral pressure in the nonlimit state region. When the internal friction angle of soil φ0 is small, the lateral pressure in the lower nonlimit state area is relatively small. When both φ0 and δ0 are small, the pressure distribution is closer to the test results and the existing theoretical calculation results.

Numerical investigation on performance of nail stabilised vertical cuts

Soil nailing is an earth retention technique commonly used for stabilising steep slopes, retaining excavations and helps in maintaining the ground surface at two different elevations. Ease of installation, economic efficiency and effective performance of soil nailed structures under different loading conditions has resulted in the rapid use of the technique in different temporary and permanent construction applications. This study deals with the finite element analysis of 6 m and 10 m high vertical soil nailed walls to evaluate the performance under static loading. The characteristics of structures are evaluated under different nail inclinations, nail lengths and different site conditions. The response of soil nailed structures under different parameters are assessed with respect to maximum horizontal displacement of the wall, maximum axial force developed along the nail length and lateral earth pressure distribution on the nailed wall. An optimum nail inclination of 15° and nail length ratio of 0.7 has been identified as best suited for a stable vertical cut.

Comparison of the plantar pressure distribution and mechanical alignment in patients with varus knee osteoarthritis following high tibial osteotomy

PurposeThe changes in the lower limb alignment were vitally important after high tibial osteotomy (HTO). Therefore, the purpose of present study was to analyze the characteristics of plantar pressure distribution after HTO, and to investigate the effect of plantar pressure distribution on postoperative limb alignment.MethodsBetween May 2020 and April 2021, varus knee patients undergoing HTO were evaluated in the present study. The peak pressure of plantar regions, medial-lateral pressure ratio (MLPR), foot progression angle (FTA), anteroposterior COP (AP-COP), lateral symmetry of COP (LS-COP), and the radiographic parameters were evaluated preoperatively and at the final follow-up. Compared among the slight valgus (SV), moderate valgus (MV) and large valgus (LV) groups at the final follow-up, the peak pressure of HM, HC and M5 regions, and the MLPR were compared; the Knee Injury and Osteoarthritis Outcome Score4 (KOOS4) including four subscales, and the American of orthopedic foot and ankle society (AOFAS) were evaluated.ResultsThe WBL%, HKA and TPI angle changed significantly after HTO (P < 0.001). The preoperative group exhibited a lower peak pressure in the HM region (P < 0.05) and higher peak pressure in the M5 region (P < 0.05); the pre- and postoperative groups exhibited a lower peak pressure in the HC region (P < 0.05); the rearfoot MLPR was significantly lower and LS-COP was significantly higher in the preoperative group (P = 0.017 in MLPR and 0.031 in LS-COP, respectively). Comparison among the SV, MV and LV groups, the SV group indicated a lower peak pressure in the HM region (P = 0.036), and a lower MLPR in the rearfoot (P = 0.033). The KOOS Sport/Re score in the MV and LV groups increased significantly compared with the SV group (P = 0.042).ConclusionPlantar pressure distribution during the stance phase in patients with varus knee OA following HTO exhibited a more medialized rearfoot plantar pressure distribution pattern than that before surgery. Compared with the small valgus alignment, a moderate to large valgus alignment allows patients to walk with a more even medial and lateral plantar pressure distribution, which is more similar to healthy adults.

An experimental investigation into soil–structure interactions of integral bridge abutments due to cyclic translations

Integral bridges are built without expansion joints to avoid many of the persistent issues with joint degradation and maintenance problems regularly experienced by traditional bridges. In the absence of expansion joints, the cyclic thermal displacements of the integral bridge would be transferred unmitigated by the joints to the abutment resulting in accentuated soil–structure interactions. Previous studies have mainly focussed on the rotational mode of integral abutment movement while the translational mode of movement and backfill deformations have received much less attention. This paper presents the results of laboratory tests conducted on a semiscale (1:2) physical model, which was designed using dimensional analysis to achieve field stress and strain similarity with a full-scale 1.92 m high-prototype integral abutment. The comparative effects from five tests covering low to high cyclic translation amplitude on backfill surface settlement and heave, and lateral earth pressures behind the abutment were investigated over assumed 120 seasonal cycles. Asymptotic settlement depth of the backfill was obtained in each test. Full passive failure surface was observed when the cyclic translation amplitude of the test exceeded the threshold amplitude. The findings also suggest that the settlement depth seemed to be linked to the development of passive failure surface in the following sense—the asymptotic settlement depth in those tests which developed full passive failure surface would attain the same (ultimate) asymptotic depth; conversely, when the passive failure surface had not or only partially developed in that test, the asymptotic settlement depth was dependent on the cyclic translation amplitude, but it was less than the ultimate observed for full passive failure surface. Lateral earth pressure only stabilized to an asymptotic state for the test with the lowest cyclic translation amplitude during the 120 cycles. Shakedown limit state was observed for this case. At larger cyclic translation amplitudes, the lateral earth pressure did not stabilize but continued to evolve with the elapsed cycles, and shakedown limit state was not observed for these cases.

Experimental evaluation of the size and distribution of lateral pressure on the walls of the excavation support

The paper presents the results of a research experiment that aimed at verifying the size and distribution of earth pressure acting on the excavation support with reference to commonly used theoretical solutions. The tests were carried out on the object in its full scale. For this purpose, a 6 m deep excavation was made in the testing ground. It was secured with a support system i.e., a point chamber consisting of corner columns and a system of three rows of fin plates. The tests relied on various measurement techniques. The earth pressure was measured with sensors specially designed and manufactured for this research experiment. Simultaneously with earth pressure measurements, there were measured stresses in the support plates with the use of strain gauges and deflections using laser scanning and a calibrated measurement patch. The tests were conducted for three months, with different backfill load. The measured values of earth pressure increased in a manner similar to the values of hydrostatic thrust, reaching max. 30 kPa before making the excavation and 25 kPa after making the excavation and assembling the support. The results were consistent with the values determined in line with commonly used theoretical solutions. The stresses caused a 15 mm deflection in the plates. Backfill load significantly affected the value of thrust down to a depth of approx. 4 m but did not cause a further increase in the deflection in the plates.